Trees deciduous. Leaves alternate; stipule caducous; leaf blade base usually slightly oblique, cordate, truncate, or rounded, margin usually serrate or sometimes entire, often with hairy domatia in axils of veins. Inflorescences axillary, cymose, 3- to many-flowered. Bracts adnate to inflorescence peduncle, band-shaped, large, persistent. Flowers bisexual. Sepals 5, with adaxial nectary at base. Petals 5, white or yellow, imbricate. Stamens many, free or connate into 5 fascicles; anthers 2-locular, dorsifixed; staminodes when present petaloid, tightly enclosing style and stigma, alternating with petals. Ovary 5-loculed, ovoid, usually hairy after anthesis; ovules 2 per locule; style glabrous; stigma apparent, 5-lobed. Fruit a nut or capsule, globose, obovoid, ellipsoid, or ovoid, pericarp usually hairy, mostly woody or fragile and indehiscent, rarely leathery and dehiscent when dry. Seeds 1 or 2.
Herbs often annual, small, usually glabrous. Roots fibrous. Stems erect or ascending, sometimes ± stoloniferous at base. Leaves opposite, fused at base to form short sheath, flat or terete, margin entire. Inflorescences axillary, cymose, often shorter than subtending leaf, 1- to few flowered. Flowers bisexual, (3 or)4- or 5-merous, inconspicuous. Sepals free, spurless. Petals inconspicuous, free, dull white, greenish, pinkish, or yellowish, often translucent, sometimes shorter than sepals. Stamens as many as petals; filaments filiform. Carpels free. Stigma terminal. Follicles 1- to many seeded, dehiscent along adaxial suture. Seeds smooth, papillate, or striate.
Trees to 150(–300+) dm. Leaves deciduous, distichous; stipules caducous; petiole not winged; blade mostly ovate to orbiculate, base cordate to truncate, usually asymmetric, sometimes caducous. Flowers actinomorphic; sepals valvate, bases sometimes coherent, abaxially hairy [glabrous], adaxially usually densely pilose to villous; petals cream to yellow, lanceolate to oblanceolate; stamens usually in 5 fascicles [+ 5 separate stamens]; staminodes [0–]5, similar to, smaller than, petals; ovary sessile, (3–)5-carpellate, ultimately 1-celled; styles 1 per ovary; stigmas 5-lobed. Fruits nutlike, indehiscent. x = 41.
"Fls 5-merous; stamens numerous, distinct or often united into 5 antepetalous bundles, in our native spp. the innermost member of each group modified into an oblanceolate or spatulate, petaloid staminode; style dilated into a shallowly lobed stigma; ovary tomentose, with 2 ovules in each of the 5 locules; fr tomentose, indehiscent, nutlike, 1–2-seeded; trees with broad, petiolate, palmately veined lvs very oblique at the base, and fragrant, white or ochroleucous fls in axillary cymes, the long peduncle adnate about to the middle of a characteristic narrow, elongate, short-petioled, foliaceous bract. 50, mainly N. Temp."
SELECTED REFERENCES Ashby, W. C. 1964. A note on basswood nomenclature. Castanea 29: 109–116. Hardin, J. W. 1990. Variation patterns and recognition of varieties of Tilia americana s.l. Syst. Bot. 15: 33–48. Hickok, L. G. and J. C. Anway. 1972. A morphological and chemical analysis of geographical variation in Tilia L. of eastern North America. Brittonia 21: 2–8. Jones, G. N. 1968. Taxonomy of American species of linden (Tilia). Illinois Biol. Monogr. 39: 1–156. McCarthy, D. 2012. Systematics and Phylogeography of the Genus Tilia in North America. Ph.D. dissertation. University of Illinois, Chicago. Pigott, D. 2012. Lime-trees and Basswoods: A Biological Monograph of the Genus Tilia. Cambridge and New York.
|Basswood, lime tree, linden, tilleul [Classical Latin name]|